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    <title>Document</title>

    <style>
    #box1{
        background-color: yellow;
    }
    #box2{
        background-color: aquamarine;
    }
    #box3{
        background-color: blueviolet;
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</head>
<body>
    <div id="box1">111</div>
    <div id="box2">222</div>
    <div id="box3">333</div>
</body>
</html>